yarrow



(No Model.)

A. P. YARROW.

APPARATUS FOR FEEDING STEAM BOILERS. 7 No. 566,644. Patented Aug. 25;1896.

UNITED STATES PATENT ALFRED F. YARRO'W, OF LONDON, ENGLAND.

APPARATUS FOR FEEDING STEAM-BOILERS.

SPECIFIGATION forming part of Letters Patent No. 566,644, dated August25, 1896.

Application filed March 20, 1896- Serial No. 584,147. (No model.)

To all whom, it may concern.-

Be it known that I, ALFRED FERNANDEZ YARROW, engineer, a citizen ofEngland, residing at the Isle of Dogs, Poplar, London, in the county ofLondon, England, have invented certain new and useful Improvements inApparatus for Feeding Steam-Boilers, of which the following is aspecification.

Steam-boilers, especially those used for marine engines, are oftenarranged to be fed each by a separate steam-pump or several of theseindependent of the main feed-pump worked by the main engine or by aseparate engine.

My invention relates to means of supplying these separate feed-pumpswith heated and purified feed-water and of automatically determiningtheir action by the water-level in the boiler. For this purpose Iarrange the feed-pumps and their communication with the boiler as Ishall describe, referring to the accompanying drawings, of which- Figure1 is an elevation of these parts with the steam and water drum shown insection. Fig. 2 is a transverse section of the waterdrum.

Although I have shown this drum as it would form part of a water-tubeboiler, it is to be understood as representing part of the upper part ofthe water-space and the lower part of the steam-space in any boiler. Ilead all the water of condensation discharged by the air-pump and mainfeed-pumps F into a closed vessel A, in which it is retained underpressure, such, for instance, as thirty or forty pounds per square inch.The vessel is of such capacity as to allow for all variations of thequantities drawn from it for feed, that is to say, it is usually largeenough to accommodate all the water pumped into it while the boilerswhich it has to supply are receiving little feed and to furnish all thewater which they require when they are receiving great feed.

The vessel A is provided at the top with a pressure-gage G and a loadedvalve S, which operates as a safety-valve and allows escape of air, andthe interior of the vessel is preferably furnished with a filter for thewater passing through it, which filter may be of any known kind. Fromthe vessel A the water passes to the suction-valves of the separatepumps P, being heated 011 its way by jets of steam J blown into it, thissteam being taken direct from the boiler or from the main or 5 5 anyauxiliary engine, or it may be, as shown, exhaust-steam from the donkeyfeed-engine D when it is of sufficient pressure to overcome that of thefeed-water. There may also be in the course of the pipe leading to thepump P an adjustable loaded valve V for escape of surplus water which isnot required for feed, this surplus returning to the tank from which themain pump F draws the feedwater or being conducted elsewhere, as may berequired. Owing to the fact that this feedwater is supplied underpressure to the separate feed-pumps it may be at a high temperature whenit reaches them, and yet the feedpumps will not fail to draw the water,which would be the case if it were at high temperature, without beingunder pressure sufiicient to prevent it from becoming partly convertedinto steam when it is drawn into the pump.

The steam for working the steam-engine D of each boiler is taken by apipe 13, the part B of which within the boiler is adjusted to such alevel as to take steam not from the highest part of the steam-chamber,but from a place between the highest and lowest levels which the waterusually attains. When the water rises above the mouth of this steampipeB, water, instead of steam, goes to the feed-engine D, thereby retardingit and also constituting by its discharge from the engine an overflowfrom the boiler, until the water is again below the mouth of thesteam-pipe B, whereupon the feed-engine D resumes its usual working. Inthis way the water-level in the boiler automatically determines thesupply and the overflow.

The level of the inlet to the steam-pipe B may be adjusted in variousways, one of which is shown in the drawings. In this case it is closedat the end and has a lateral open- 5 ing to a sleeve L, which has a sidebranch with its mouth directed downward. This sleeve can be turned moreor less on the pipe B by turning a spindle II, which has an arm linkedto the sleeve and passes through a stuffing-box to an external handle.In order to provide against water entering the pipe B in case ofebullition or priming, suitable deflectors may be arranged above andbelow the mouth of the pipe. Obviously this mode of automaticallycontrolling the feed is applicable whether the feed-water be heated ornot.

Having thus described the nature of my invention and the best means Iknow for carrying it out in practice, I claim- 1. The combination with asteam-boiler and with a main feedpump for said boiler, of a closedvessel with which said feed-pump and an air-pump are connected, saidvessel having a capacity to receive the water of condensation andcontain the feed-water, a donkey-engine the exhaust-pipe of which entersthe pipe connecting said vessel with the main feed-pump, a steam-supplypipe for the donkey-engine having its end arranged within the boilerbetween the highest and lowest water-levels, a connection between thesaid closed vessel and the pipe which connects it to the main feed-pump,and a loaded valve to close communication through said connection,substantially as described.

2. The combination with a steam-boiler and with a main feed-pump, of aclosed vessel with which said main feed-pump and an airpump haveconnection, a donkey-engine to operate the feed-pump, its steam-pipebeing arranged in the boiler between the highest and lowestwater-levels, a side branch sleeved upon said pipe within the boiler,and means for adjusting said side branch so that the open end shall beat any required level, substantially as described.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses,- this 10th day of March, A. D.1896.

ALFRED F. YARROW. Witnesses:

OLIVER IMRAY, GERALD L. SMITH.

